Signaling device



1943 L. N. HAMPTON L 2,325,952

SIGNALING DEVICE Filed Dec. 11,, 1941 4 Sheets-Sheet 1 L./V. HAMPTON lNVENTORS- G a SW7.

Aug. 3, 1943. L NFHAMPTON ErAL 2,325,952

SIGNALING DEVICE Filed Dec. 11, 1941 4 Sheets-Sheet 2 L. N. HAMPTON lNl/ENTORS G G SM/TH ATTORNEY llllllll llv'lllY L. N HAMPTON EI-AL SIGNALING DEVICE Flled Dec 11, 194

Aug. 3, 1943.

Aug. 3, 1943.

| N. HAMPTON 1 m.

SIGNALING DEVICE Filed Dec. 11, 1941 4 Sheets-Sheet 4 FIG/0 FIG.

' naw/v "WENT 6.6.5M/7'H ATTORA/EV Patented Aug. 3, 1943 UNITED STATES PATENT OFFICE SIGNALING DEVICE Application December 11, 1941, Serial No. 422,508

8 Claims.

This invention relates to ringing generators and particularly to the design of a single genator which is adaptable for substantially every use to which a ringing generator is put in the telephone field.

It is the object of this invention to simplify and otherwise improve the design of telephone ringing generators, and particularly to provide a generator which is suitable for use with various instrumentalities used in telephone signaling, such as combined telephone sets, telephone linemens test sets, and the like.

This object is attained by the provision of: design features which effect a compact and highly efficient structure of reduced weight and size, and which readily lends itself for mounting the receptacle or cavity generally occupied the telephone dial of a subscribers set, or for association with other telephone apparatus such, for example, as a linemans test set, I

A feature of the invention resides in the design of a front mounting plate which serves to accommodate one or more interrupters of the type commonly used with ringing generators, in such a position, or positions, that the interrupters are capable of being driven directly by the crank shaft gear which functions to drive the rotor element of the generator. In prior generators of this type the interrupters have been independently mounted. This built-in interrupter feature tends to reduce the cost of the equipment and results in the embodiment, in a single unit, of those essential generator and interrupter elements which heretofore were designed for independent mountings. This feature which finds particular use in what are known as linemens test sets, is equally applicable to the generators employed for other purposes. as for example, the ringing current generator of a magneto type telephone set.

Another feature of the invention. resides in the use of anchoring, or fastening means for the leads which extend from the generator coils to the terminals of the spring pile-up associated with the generator. This anchoring means comprises pairs of lugs, or projections, integrally formed on the rear mounting plate between which the coil leads are inserted or confined, and which, after the insertion of the leads, crimped or otherwise pressed together to hold the leads neatly and flush with the face of the rear mounting plate. I

A further feature of the invention resides in the crank handle design which is such that the crank handle serves also to accommodate the designation strip, or instruction card usually fu nished with subscribers telephone sets.

These and other features of the invention which cooperate in efiectlng a simple, compact generator structure having a minimum number of parts, will be set forth in great r detail in the following description. which is made with reference to the accompanying drawings.

In the drawings,

l is a side sectional view of a ringirv generator of the type particularly suitable for use with a linemans test set and which embodies features of the invention;

Fig. 2 is a front view of the generator of Fig. 1 with a portion of the cover removed, showing the position of the interrupters relative to the crankshaft gear which drives the generator rotor;

Fig. 3 is a section taken along the line 33 of Fig. 2 and shows a side view of the interrupter mechanism;

Fig. 3A is a view of the interrupter assembly, partly in section, showing the integral flange or hub-like projection of the pinion and the relative disposition of the insulating and contact elements of which the interrupter is made;

Fig, 4 is a side sectional view of a hand generator similar in design to that shown in Fig. 2, but which is arranged for mounting in the dial cavity of a subscribers telephone set;

Fig. 5 is a sectional View of the ringer shown in Fig. 4, taken along the line 5-5 of Fig, 4 and looking in the direction of the arrows;

Fig. 6 is a view of the interior of the generator unit of Fig. 5 with a portion of the cover removed;

Fig. '7 is a rear View of the generator illustrated in Fig. 5 showing the rear mounting plate and the method of anchoring the generator coil leads thereto;

Fig. 8 is an enlarged section taken along the line 8-8 of Fig. '7 showing more clearly the method employed in anchoring the generator coil leads; V

Fig. 9 is a perspective view (reduced in size) of the electromagnetic structure of the generators shown in the preceding figures;

Fig. 9A is an end view of the stator structure shown in Fig. 9 and illustrates the interleaved lap joint employed in the assembly of the laminations of which the stator is made up;

Fig. 10 is a perspective view of a combined telephone set showing the hand generator mounted in the position usually occupied by the telephone dial; and

of the laminae, is magnetica of. an. alloy 'havi-ng.

V cal, like numerals will be u V and shown particularly- ,7

a rear mounting plat a front plate i7..: Elle above these rivets are Fig; 9.

Figfll is a side View of the telep'lone set shown in Fig. 10 with a section ofthe pedestal portion broken away to disclose the manner in which the generator i incur to the set.

lhe' electromagnetic tors illustrated in the draw it madei'ofi silicon steel terleaved lap'joint. The int I the laminations constitute the magnetic leg ii on which the output coils 42 are carried. The

coils l2 are preferably for-.1 wound. The stator leg H, in effect constitutes a rhagn 1c shunt which, by virtue of the inte constituting an improvem nt over imilar S'fiilltures which resort to a butt joint. The laminae of the stator iii are so formed that wh n as-- sembled, they effect a structure having a pole are substantially equal to the pole pitch, is,

in-the-case of the lei-polar -cachine disclosed,

e wider i21 he generator in substantially- 18 3 degrees. creases the intenialreactance O1- that iti-provides a return magnetic path wh the: rotor. poles are in line \'-.-'lt11- tl13'Stat0lpole eorrters;. In other words, the. pe "lent magnet flux has an augmented leakage path prin T pally through ironic-ve n when e flux does-not interlock With the coil. The rotor is-isa-oy" 'd-rical permanent magnet ce and work l.-gh coercive i0" factors The permanent ma 7 on the shaft M which is of non-magnetic steel. ,"Ehe externalsurf. e of th magnet is ground: to" secure. accurate mechanical dimensions The use of a. coinple cylinder for the field-i magnet, 4 instead: of ploy eliminates the voltage peaks which would occur withv the'latnrtype of. rotor, when theedges of the'poles line-up with thestato' pole tips. It; i also minimizes variations in the mechanical" torque rec red to-dr-ive thegenerator. v i v ted 1 :3 the rotor torts-magnetized in place, C-llfi-i? flux-z output or the permanent ma fore, the power cleli-vered'by the polesof powerfulelectroinag andthere- The on the of the. generator in line with the.

stator pole. centers, nd sin cient flux passed, through thestrue e'to fully saturate the core through the coils, so that fun; is forced through the permanent magnet and :netizes it place.

position by urea got four scr vs orrivets ,5, or their equivalents, located at tn-e four corners of tho tructurei Sir-icethe structiires illustrated in the seve figuresoftherd-rawirrgs a old A ntsthroughout: t

vets i5 mount.- or secure" the. stator is through the front andrea spective'ly; seas-to hold tla'es together with laminations clamped 'norebetwe'enr These rivets are indicated by th numeral in Figs! 2,5, 6 and. 7: Whereas the holes which receive looted by the numeral ii 55 in utions, extend on: the" vertical center line of each plate iii and I 'i, and located near t e top (viewing Fig alsalient o, creasing The laminationso'f the st tor iiiarehold in a 2 a held between which serve to V ites i'land it, re-

1 and i) there are provided two bearings effected by the apertured circular bosses is and it, into which extensions of the rotor shaft i i extend, and in which the shaft is permitted to rotate freely. On the front end of the shaft i i there is tightly fitted a pinion gear of relatively small diameter which, as will appearrnore fully from a later description, meshes with the drive ear 2!". V

On the same center lines on which the bosses i3 it are located, and spaced from these .bosscs-are two other cylindrical apertures effected by the cylindrical bosses 2; and in the platesjil' and'iil respectively, the fair or of which cc cti ates a tie-aring in which one end of the crankshaft is adapted to rotate freely. Interpose'd'h'etween the'inner face of the bearing effected icy the boss- 2 3 011 the front plate ii and the forward portion of the crankshaft 23 is a collar 23 which is formed integral with the large drive gear iii. The rear edge of collar is so formed as to present two helical camming sur-' faces which normally meshwith correspondingly shaped camming. surfaces of the. cam fol-lower 2?. The cam follower 2'3 is pinned. to the shaft: 25 by means of pins whoseends fitted into oppositely disposed slots inv the cam fol lower. The rear end of the shaft issored. so as to accommodate the stud whichservos apurpose tobe" indicated hereinafter. end of shaft 25 is adapted to rotate freely in the bearing effected by the cyl-indrical'hoss 22;

The forward endofsh-a-ft. 25 is provided: with apair'of oppositely disposed; pins or integral- 1 projections which fit loosely into'oppositely 'dise posed slots- 33 in a boss 34 formed integral with the crank- 35. The boss-E lis. apertured. to allow the cranhfifi to be slipped over the for-ward end of the shaft 25. The extreme front end-of the shaft 25 is thre dad .toaccommodate the nut 31, which; with the'washer 38, fits into adepression 39inthe outer faoe'of the crankfili. After the crank. 35 is slipped over the end of shaftiiii in suchamar-mer that the 'slotsi fifi-receive the pins 32 ofv the shaft, thenut 31 is v screwed up on the shaft end, thus firm-1y securing the crank. to. the shaftr V r g ,The apparatus thus-far described functions the following manner: 1

, Whenthehandle i-Ei (Fig, 4.) or (Fig. l

ofthe crank 35 is rotated, theshaft ences a similar movement due to the engage .ment of the shaftpins with the crank slots 33; The large drive gear Ell, with its integralcol-- lar 2-3, is'freely mounted on the shaft 2a and doesinot immediately rotate. The sleeve 27,. be

ing pinned to shaftiidoes rotate, however, so

that a. camming: action takes place between the helical camming surfaces of the sleeve 2.? and 'of the inner edge of the gear collar with the result that, as the shaft continues to rotate, it is moved longitudinally to the, right; (viewing Figs.- 1 and 4) causing the stud 35 to experience a: similar movement which results in: the operation of contact springs '42 (Fig. 4) or (Fig. 1);

These Contact springs, which are mounted on theouter faceof the rear plate it, as shown, perform functions-well known tothose skilled in V the art.-

The extent to which shaft it moves to the rightiFigs. 1- and' 6) is limited by the boss; r flange 34 on crank 35 which abuts gear 25,- and is of such magnitude that the longitudinal move ment of the shaft is insufiiciehi; to cause sleeve -2Ljto disengage from collar 26, andalso insufii- The rear cient to cause boss 60 (Fig. 4) to contact crank 35. Thus the shaft 25 and the drive gear 2| become locked and the latter is then driven by the shaft by virtue of the engagement of the camming spirals of sleeve 21 and gear collar 25 which can no longer rotate relative to one another. The drive gear 2| accordingly rotates and, through the pinion gear 20, drives the permanent magnet rotor I3 as long as the crank 35 is rotated. Rotation of the permanent magnet l3 between the poles of stator l causes a current of substantially pure sinusoidal wave form to be generated in the output coils 2 l As clearly shown in Fig. 7, the leads $2 and 63 of the output coils I2 are connected to terminals of the spring pile-ups mounted on the rear plate l6. The leads 62 and 63 are held neatly, in close proximity to the outer face of the rear plate 16 by means of integrally formed lugs 10 and H on the outer face of the rear plate. These lugs are cast integrally with the rear plate. They may be formed by slotting-the mold in which the plate 55 is cast, the metal which occupies the slots during the molding process constituting thelugs 'Hland H when the plate is removed from the mold. The leads 62 and 63 are inserted between the pairs of lugs Ti) and II, respectively, and the lugs are then crimped, or otherwise pressed together over the leads as clearly si.v wn in Fig. 8. In this manner the generator coil leads are neatly and securely fastened to the rear face of the plate l and held in close proximity thereto.

When the crank handleis released, the springs of the spring pile-ups 42 or 42' exert suihcient pressure on the stud 3-5 to drive the shaft 25 back to its normal position. The camming spirals of sleeve 21 and collar 26 assume their original condition of mesh during the return longitudinal movement of the shaft 25.

The generator shown in Fig. 1 is equipped with a folding handle which distinguishes from the handle furnished on the generator of Fig. 4. These handles obviously are interchangeable though the former type is preferred with generators to be used in conjunction with telephone linemens test sets, whereas the rigid type is preferred with generators used with subscribers sets.

The following description is directed principally to the design of crank handle shown in Fig. 4. The crank 35 may be molded or otherwise formed so as to consist of a main body portion and a liandie supporting portion extending therefrom. The main body portion is circular in contour and has its outer face recessed to provide a seat for the circular designation, or instruction card 88. Theupper edge of the main body portion of the crank which defines the recess, or card-holding compartment issiightly curved over to provide a lip which serves to retain a circular Window 89 of transparent material in position over the card 38. Thus, the generator crank, besides serving as a medium for actuating the generator rotor, also serves as a designation cardholder, thus obviating the need for a arete card-holder and associated means for mountjng it on the subset.

The generator equipped with the rigid type crank handle and shown in Fig. 4 is illustrated in Figs. and 11 mounted on a telephone subset. As illustrated in Fig. 11, the front face of the pedestal portion of the set 15 is provided with a circular cavity or cup-shaped depression which is defined by the base 16 andthe circular rim H. The base 16 is provided with three holes I8, only one of which is shown in Fig. 11, which accommodate screws 19. The screws 19 pass through the base I6 and engage the threaded holes in the generator base plate 16. The diameter of the circular depression in the front of the telephone subset is suchas to conveniently accommodate the plate I6. The generator unit is set in the circular cavity in such a manner that the holes 88 in the generator plate I5 are aligned with the holes 18 in the base 15. The screws 19 are then made up tight. In this manner, the generato is securely held in position on the telephone set in the location usually occupied by the telephone dial. The numeral 90 identifies the apparatus supporting base of the combined set while the pedestal portion is indicated by the numeral 9|.

A cover 50 for the generator unit is provided, whose circular rim fits into the oifset at 5| in the rear plate l6. locate the cover longitudinall with respect to the generator unit, and the proximity of two of the bosses 92 to the bosses 93 on the front plate I! locates the cover radially. The cover is held in position on the rear plate It by means of two screws 82 which fit into recesses 83 in the plate [6 and are screwed into tapped holes in the bosses 84.

As previously mentioned, the ringing generator of this invention may be furnished with one or more interrupters whose functions are well known to those skilled in the art. Heretofore, such interrupters were mounted independently of the generator as a separate unit. In accordance with a particular feature of this invention the front plate I! of the generator uni is provided with two sets of integrally formed bosses, each set including a rectangular boss I00 and a circular boss lfll. The rectangular bosses provide mountings for the spring pile-up of an interrupter assembly, while the circular bosses provide mountings for the interrupter unit per se. These two sets of bosses are clearly shown in 2 and 5, the former figure showing one of the interrupter assemblies position on its respective set of mounting bosses.

The interrupter assembly consists primarily of a pinion gear I20 having a cylindrical flange or hub-like projection I50 of lesser diameter extending therefrom and integrally formed therewith. The flange and gear, preferably of steel, are provided with a centrally located axial bore which accommodates the stud !2[ which is fitted tightly in a suitable hole in the front plate H. The stud constitutes a bearing upon which the pinion is adapted to rotate freely. The flange or shank of the pinion ISL serves to mount a ringshaped slotted contact element 122 of hard copper, and a similarly formed insulator element [23. The outer end of the pinion flange is formed over or set in such a manner as to securely hold the contact !2 and insulator I23 in position on the flange. An insulating ringshaped washer I24 is interposed between the shoulder of the pinion and the contact element. By virtue of this construction the pinion and its associated contact and insulator elements rotate as a unit.

A spring pile-up, mounted on the rectangular boss I90, consists of a plurality of phenol fibre spacers 125 and a steel. spacer I21 which are securely fixed to the boss ie'iil by means of two machine screws IZS which pass through aligned holes in the several elements I 25 and I2! and are screwedinto tapped holes in the boss I Bil. A con- Four bosses 92 on the cover,

tactspring; m7 is provided an. .ofisetreotanguiar lug which: islocatedibetween tW.O.1 l-13131EITTiII- dilating. spacers i25 and". is providedi with. two holes placed similarly to those in the spacers which permitthe shanks ofnthe screws 12.8- to pass there-th-rougl-i. Thus the rectangular lug the contact spring: l t-l: becomes, in eifect, an element ofthespring pile -upl The spring it? is providedswi th a contact: at its free end which is adapted toride overthe: periphery of. the insulator :23; A second contact spring iii--35, mounted in. the spring pileeup; is. arcuate in: form; having; a substantially semi-circular per:- tion Jhichis'located immediately above the contact element i 22: and is provided with an irregularl-y formed contact end which rides on. the

upper face of the contact I22-near its outer edge when the interrupter is rotated. Each machine screw 428: is provided with a cylindrical bush-- ing o sl'eeve, not shown. jEach of'the springs terrupter which functions to interrupt the current generated by the-generator at a frequency determined-by the number of slots in the contact elementlEZ and its assoiated insulator i 33. This arrangement provides a-positive drive for the interrupteit andresults ina self-contained generatonand interrupter assembly;

Inithegeneral disclosures, Figs; 4-, 5,

the: rectangular andcircular bosses lfldand ldl upon. which. the-interrupter. assembly is mounted are illustrated in Fig. 5; In Fig, 2--only one interrupter. is showninposition on the generator front plate I'Lit being understood that therighthand rectangularand circular bosses lot and it? may-heusedto mount a second interrupter mechanism, if required.

As hereinbefore indicatedthegenerator of this invention is suitable for use in numerous instances-in. the telephonefield requiringusuch a device.- In Figs. 1- and 2 the generator is mounted: on an angle'braclcet. i453 which is secured thereto by means of screws. Across the upper end of this bracket there is mounted a terminal :1,

strip- Ml. which accommodates a plurality of terminals Hi2 to which the leads extending from the generator coils and from the springs of the spring 7 pile-up42f are secured. The leads are bunched at:the, center of the strip i il'by means of'a strap,

not. shown, from which the leads are'fanned out to; their respective terminals Hi2 from which connections to a test set may be made.

As previously indicated, the operating cranl; handles illustrated in Figs. 1 and i, while difieringin design, may be interchanged if required. The crank handle shown in Fig 1 is particularly desirable when the generator is to be usedin. connection: with a linemans test set, whereas the oneshown inFig. l is suitable for use in cases where the generator is to be used in connection with a combined'telephone handset, as. shown In the former case the desigin-Figs; .ldand l1. nation card, illustrated in Fig. 4, is not required. As shown in Fig. 1, the handle assembly col-- and 6, the-interrupter mechanism is not shown, though iii.)

prises a cranktii', a handle ififl a circular insulating washer 9t and a metal piece 8; The last element is generally: circular'in shape and is provided with an integral cylindrical projection 34 which corresponds to the integral projection 34 of Fig. i. This projection 34'" is slotted: at 33 in the same manner that the projection 34" of Fig. 4 is slotted, so as'to enable it to fit over the. shaft with the. pins 32; engaging the slots 33; The elements, 8, 9,.and 35 are held together asa unit by means of rivets, one of which is shown at T. The crank portion 35' isprovided with two integral, spaced, righteangular projections 6, between which one end of the handle is mounted for rotationon a pin: 5'. The pin 5 may'carry a coil spring which functionstonormally hold the handle 49 in the full-line position indicated in Fig.1, that is, folded down. When the generator is to be actuated, the handle ld" is moved to'the position indicated by the horizontal outline shown in Fig. 1, and the crank assembly rotated.

What is claimedis: Y

1. In combination, an electric current generator comprising a rotor, a coil bearing stator, a front and rear mounting plate and means for mounting said rotor and coil bearing stator between said plates, and an interrupter mounted directly on one of said mounting plates, driving means for said rotor comprising a shaft and a gear carried thereby, and a gear fixed to said-in-- terrupter permanently meshing with the gear of said driving means whereby said interrupter and said rotor are separately driven by said shaft through the medium of the gear associated therewith.

ator comprising a rotor, a'drive shaft therefo ga coil bearing stator, a front mounting plate, areal mounting plate," means for securing said rotor" for, means for mounting said interrupter assem bly directly on one of saidinounting plates com f prising integrally formed bosses on said plate,

and means for securing said interrupting contact device and said contact springs to separate ones of said bosses, and means forcoupling said inte'rrupting contact device-to said drive shaft comprising a pinion fixed to said interrupting contact and a gear associatedwith' said drive shaft, said pinion and said gear being directly'and'pen manently in mesh.

3. In combination, a ringingcurrent generator comprising a rotor, a stator, apair'of output coils on said stator, a pair of mounting'plates between which said rotor and stator arem'ounted, a drive shaft having a gearcarried thereby, a rotor'shaft having a pinion gear'thereon; normally meshing with the said drive shaft gear, manually operable means for driving said shaft to cause said rotor to rotate relative to said statorwhereby signaling current is generated in the output-coils of said statonand means for interrupting the current output of said stator coils comprising an interrupter mounted directly on one of said mounting plates and having a pinion gear in permanent mesh with said drive shaft gear.

4. In combination, a current generator comprising a rotor, a stator, a pairof output coils on said stator, a front mounting plate, arear mountlng plate, means for clamping said rotor and stator between said front and rear mounting plates, a shaft on which said'rotorxismounted, a

drive shaft',.cylinclrical bosses castintegrally with '2. In ccmbinationfan electric currentjgenersaid front and rear plates which constitute bearings for said shafts, a gear carried by said drive shaft, a pinion gear fixed to said rotor shaft and normally meshing with said drive gear, manually operable means associated with said drive shaft for rotating said rotor relative to said stator whereby current is generated in said stator output coils, and means for interrupting the output current of said coils comprising a rotatable interrupter, contact springs engaging said interrupter having circuit connections with said output coils, independent means for mounting interrupter and said contact springs directly on said rear mounting plate in close proximity to said drive shaft gear, and means comprising a pinion gear associated with said interrupter permanently meshing with the drive shaft gear for imparting the rotational movement of said drive shaft to said interrupter.

5. In combination, a current generator comprising a rotor, a stator, a pair of output coils mounted on said stator, a drive shaft, a shaft for said rotor, end plates, means for clamping said rotor and stator between said end plates, bearings for said drive and rotor shafts comprising hollow cylindrical bosses formed integrally with said plates, a pinion gear on said rotor, an interrupter assembly comprising interrupter contacts and contact springs operatively associated therewith, a pinion gear associated with said interrupter contacts, means comprising bosses formed integrally with one of said plates for supporting said interrupter assembly, manually operable means for rotating said drive shaft, and means for coupling said drive shaft to said rotor and to said interrupter assembly comprising a gear carried by said drive shaft and permanently meshing with the pinion gears associated with said interrupter contacts and with said rotor shaft, whereby said rotor and said interrupter contacts rotate coincidentally upon the operation of said manually operable means, the former to generate current in said output coils and the latter to interrupt the generated current.

6. In an electric current generator, a rotor, a stator, output coils mounted on said stator, a front mounting plate, a rear mounting plate, means for clamping said stator and said rotor between said plates, contact springs mounted on said rear mounting plate, conductors extending from said output coils to said contact springs, and means for fastening said conductors to said rear plate comprising pairs of complemental lugs formed integrally with said rear plate and projecting outwardly therefrom, th lugs of each pair being so disposed relative to one another as to permit the insertion of one of said conductors therebetween and adapted to be thereafter crimped so as to enclose said conductor and hold it in place against the face of said rear mounting plate.

7. In combination, an electric current generator comprising a rotor having a gear fixedly associated therewith, a coil bearing stator, front and rear mounting plates, means for mounting said rotor and coil bearing stator between said plates, a rotatable interrupter mounted directly on one of said plates and having a gear fixedly associated therewith, and means for driving said interrupter and said rotor simultaneously comprising a manually operable drive shaft having a single drive gear associated therewith and in permanent mesh with the ears associated with said rotor and with said interrupter.

8. In combination, an electric current generator comprising a geared rotor, a coil bearing stator, a front and rear mounting plate, means for mounting said rotor and coil bearing stator between said plates, and a geared interrupter mounted directly on one of said mounting plates, and common driving means for said rotor and said interrupter comprising a rotatable shaft and having a single gear associated therewith in permanent mesh with the gears of said rotor and interrupter at different points on its periphery.

LEON N. HAMPTON. GEORGE G. SMITH. 

